Recently, asbestos (fibrous silicate) has become a problem since it has adverse effects on human body. Specifically, a company has disclosed to the public that workers who have been involved in producing asbestos or handling asbestos develop health problems such as lung cancer and mesothelioma at a high incidence rate. In addition, it has been reported that inhalation of asbestos powder dust may cause health problems mainly including asbestosis, lung cancer, and malignant mesothelioma.
Asbestosis is a kind of pulmonary fibrosis (pneumonoconiosis), which is a disease that causes fibrosing lung.
There are many factors that cause the fibrosing lung, including other mineral powder dust. However, pulmonary fibrosis caused by exposure to asbestos is classified especially into asbestosis. Lung cancer is developed mainly by physical stimulation of asbestos fibers taken up in alveoli of the lung. The level of carcinogenicity of asbestos varies depending upon the type, thickness, and length, of asbestos. Malignant mesothelioma is a malignant tumor of a pleura surrounding lung, peritoneum surrounding organs such as liver and stomach, and the like part.
Examples of asbestos include chrysotile (white asbestos), crocidolite (blue asbestos), amosite (brown asbestos), anthophylite, toremolite, and actinolite. More than 90% of the use of asbestos is for building materials. In other examples, asbestos is used for sealing materials for chemical plant setup, and industrial products such as friction materials. Manufacture and handling of building materials, friction materials, and adhesives containing asbestos have been banned since Oct. 1, 2004. However, there were circumstances where a large amount of asbestos was used in the past, and asbestos has remained in many buildings.
Detection of asbestos is performed by the following method. That is, for the detection of asbestos in the air, asbestos is trapped by a filter when the air is taken in by a pump, and the filter is subjected to achromatization by using acetone to observe the filter through a phase microscope. For the detection of asbestos in building material, a sample is collected by appropriate amount from a building material to be analyzed, and the collected sample is subjected to grinding, pulverization, heating, and/or other treatments according to the form of the building material and the state of a substance that coexists with the building material to prepare a sample to be analyzed. Next, the sample to be analyzed is subjected to qualitative analysis by disperse dyeing analysis method through a phase microscope and qualitative analysis by X-ray diffraction analysis so as to determine whether the sample contains asbestos. The sample which has been identified as the one containing asbestos is treated with formic acid to prepare a sample to be subjected to quantitative analysis. Then, the sample is subjected to quantitative analysis by X-ray diffraction analysis method that uses base standard absorption correction method to find the amount of asbestos contained and calculate the percentage of asbestos content (see Non-Patent Documents 1 and 2).
However, observation through a phase microscope requires advanced skills and requires a considerable time. Therefore, it is difficult to perform many operations at the same time. Besides, X-ray analyzer is very expensive and cannot be used easily by anyone.
[Non-Patent Document 1]
Working Environment measurement Series No. 3: Manual of Fibrous Substance Measurement, Japan Association for Working Environment Measurement, Jul. 28, 2004
[Non-Patent Document 2]
Method of Analyzing Asbestos Content in Building Material, Kiankahatsu (Ministry of Health, Labour, and Welfare, Labour Standards Bureau, Industrial Safety and Health Department, Chemical Hazards Control Division) No. 0622001 , Jun. 22, 2005